208v 3ph Receptacle calculated load

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InspectorPatches

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Electrical Inspector/plans reviewer 1
Hey everyone, I've got a question that I cant seem to find clarification in the code book regarding 3 phase receptacles being calculated at 180va. I have a panel calc submitted for plan review. They are calculating numerous 3ph 208v receptacles at 167va on each phase. Where they got that number I don't know. The area is for a lab and my gut tells me that the 3ph receptacles should be calculated by NEC 220.14(A), Specific loads and appliances, and not by NEC 220.14(I). To me I feel like there's info being intentionally left out so they can get approval to add this new equipment. Is there a NEC section that refers to 3 phase receptacle load or would it just be 180va if no info on specific appliances is provided?
 
I think the purpose of 220.14(I) is for single phase 120v receptacles, even though it is not stated

Three phase outlets are typically for a specific appliance.

Unless you are using a three phase plug to feed many outlets with a multiwire branch circuit, which should be calculated as 180VA for each receptacle served.


I am working on a Lab project right now where we are using 14-20 plug (2 hots+neutral+ground) to feed receptacles in a lab bench, and I will be calculating the load by 180VA for each duplex
 
LarryFine said:
You could use 180va x 3, or 540va, to be conservative.
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I just cant imagine any 3phase equipment drawing such low amp. I could be completely wrong though. I'm a bit concerned that the breaker will overload while the furnace is on and 2 or 3 of the 3ph outlets running depending on their draw. And even yet, per code if the receptacle is on the same yoke than it would be just 180 regardless of phases, correct?
 
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